Cooking can be a messy process. Particularly when cooking in large quantities. Particularly when cooking raw meats. Particularly when cooking in a food service setting, where numerous meats are being simultaneously prepared at various states of readiness, and under tremendous time pressures. Cooking can be a messy process. And that is why, according to Centers for Disease Control and Prevention, every year, about 76 million people in the United States become ill from pathogens in food. Of these, up to 5,000 die. That is, every two hours, a person somewhere in the United States dies of food poisoning. The most vulnerable members of our community—elderly, children and people with weakened immune systems, who are dependent on organizational food services of adult homes, schools and hospitals, are at the highest risk of lethal food poisoning. Any new methods or innovations that can reduce this risk and save even a single life, are urgently needed by society and, are quite literally, the matter of life and death.
Some of the worst poisoning cases occur when pathogenic microorganisms that are usually found in raw meats, contaminate prepared foods. A major vector of such contamination is a meat thermometer.
Meat thermometer is a common and frequently used tool that can usually be found in a cylindrical pen-like open-top case, clipped to the pocket of almost every cook and food service worker. Proper food safety procedures and legal responsibilities of food service providers require constant monitoring of the internal temperatures of prepared meats. For example, to ensure that most disease-causing bacteria are destroyed, meats, such as beef and lamb, must be heated to the internal temperature of 145° F. Poultry dishes, stuffings and casseroles must reach internal temperatures of above 165° F. But many dishes can not be overcooked either, and must be removed from heat soon after the safe internal temperature is reached. Thus, a cook must frequently, sometimes every minute or two, insert a thermometer probe into the yet-uncooked meat to monitor the rate of preparation. When not one, but several meats are cooking simultaneously, as is most often the case in food service kitchens, the rate of temperature measurements required of the cook increases dramatically. Frequently, several meats in the kitchen are at different stages of preparation and a single thermometer is used to probe rare and cooked meats.
Whenever in the course of the temperature reading, the probe portion of the thermometer is removed from the uncooked meat, small particles of raw flesh, bodily fluids, and millions of microorganisms remain adhered to the surface of the thermometer. In the ideal kitchen, the ideal food worker would then proceed with carefully washing and sanitizing the thermometer, and then carefully drying the surface before placing the thermometer back into the storage case, clipped to his or her gown pocket. The ideal worker then continues the process of cleaning with the same vigor again and again, each time that the temperature reading is taken. But not every food worker is ideal. And things are often hectic in public service kitchens. In reality, even the most attentive workers, in a hurry, will occasionally put a dirty or casually-wiped thermometer into the case.
Some of the contaminants, such as raw meat particles and bacteria from the surface of the thermometer, will then adhere to the inner walls of the thermometer case, contaminating the case. Even if the meat probed was well cooked-through and free of any living microorganisms, the particles of cooked meat, adhering inside the case, will, within hours, become the rotting breeding ground for millions of bacteria. If the dirty thermometer is inserted into the clean case even once, the case will become forever contaminated. Afterwards, even if the thermometer itself is always properly sanitized after use, it will become re-contaminated again and again after each insertion into the contaminated case. When such a re-contaminated thermometer is taken out of the case to probe prepared foods, the bacteria from the surface of the thermometer remains in the food. This leads to violent illness, deaths, and tremendous legal liabilities.
The problem with standard pen-like pocket-clip thermometer cases available on the market today, is that contamination of the case is impossible to detect. The common design of such a case is a long and very narrow tube. It is nearly impossible for the user to notice any stains or food particles on the dark inner surface of the case.
An even bigger problem is that contamination inside of the standard case, even if noticed, or known, is nearly impossible to clean. Proper cleaning involves at least a good scrubbing and washing of the surface to mechanically remove the decomposing food particles and microorganisms from the surfaces of the case. The surfaces must them be thoroughly and completely dried to prevent the accumulation of moisture, favorable for bacterial and mold growth, inside of the case. However, the narrow confines of the bore allow no access for quick, simple and, most importantly, reliable cleaning and drying of the entire internal surface.
Yet another problem associated with most top-loading thermometer cases is the risk of botulism. Botulism is one of the most lethal food poisoning varieties, resulting from neurotoxins, released by Clostridium botulinum. Clostridium botulinum is anaerobic bacteria, meaning that it grows best in sealed, low-oxygen environments. Presently, some thermometer cases are completely sealed, aside from the insertion aperture, while others also have an aperture on the distal end. However, when the thermometer is inserted into the casing, the distal end aperture becomes tightly plugged-in by thermometer's probe, while the insertion aperture is plugged in by the thermometer's dial or calibration knob. Thus, a sealed-off space is created inside of the case. If the thermometer was not properly sanitized before being placed into the case, or if food particles from prior thermometer insertions remain inside of the case, then, as described above, common types of aerobic bacteria will start growing inside of the case. These bacteria will eventually use up the oxygen in the sealed-off space and allow the lethal neurotoxin-producing anaerobic bacteria, such as C. botulinum to grow on and around the thermometer probe. The structure of the present invention solves this problem.
The dangers of contaminated thermometer cases and the accompanying legal liabilities are well known to food service providers. Aside from the moral and business issues of poisoning one's customers, negligence law generally puts a heavy burden of duty on food service providers to continually ensure the safety of their patrons. Breach of this duty can lead to prolonged and expensive litigation and very unfortunate legal outcomes, including imprisonment, fines, and tremendous civil liability. And that is why, instead of using thermometer cases of questionable cleanliness, responsible organizations often choose to discard and repurchase their entire stock of thermometers every few weeks. Quality food thermometers are not cheap, and this approach is obviously an extremely expensive one. Furthermore, such approach does not prevent the contamination of the case and subsequent poisonings within the first several weeks of thermometer use, before it is discarded. Thus, most thermometer purchasers would prefer a possibly more expensive thermometer and storage case, but one that can stay verifiably clean, and be used for a long period of time, without the fear of unexpected and unpredictable poisonings and liability.
Measuring anal temperature is also a messy process. As is measuring oral temperature, armpit temperature, ear temperature, or for that matter temperature on any part of an ill person or animal. Pathogenic bacteria present in body fluids and skin of a person, attach to the surface of the thermometer. When the thermometer is placed into the storage case, the microorganism-infested tissues, including skin flakes and oils contaminate the case in the same way as described above with the meat thermometers. Once the case is contaminated, the thermometer will pick up bacteria from the case each time that it is put in contact with the case. The bacteria will then be transferred to another patient or family member who uses the same thermometer. Since medical thermometers are usually used only when a person feels ill, most thermometer users already have immune systems weakened by a disease. In such a common situation, contaminated thermometer may well be the cause of a secondary infection. Secondary infections are extremely dangerous, and frequently fatal.
Some kinds of bacteria, the most dangerous and very common kinds, can lay dormant for years inside of a thermometer case. Spore-forming forms, such as Bacillus, cause the most dangerous and diverse bacterial ailments, including anthrax, meningitis, endocarditis, respiratory, and urinary tract infections, and food poisonings, among others. Bacillus spores can survive for hundreds of years, scattered around in a thermometer case without any access to water or nutrition. As soon as the thermometer, infected with these dormant spores contacts the tissues or body fluids of a living organism, the bacterial spores spring to life, rapidly multiplying and infecting the user of the thermometer. Most disinfectants do not work on bacterial spores. The only reliable way to get rid of the spores is to scrub and/or wash them out with hot water and soap. But tubular side-loading cases currently used to store modern medical thermometers (such as the case described in U.S. Pat. No. D526,585) are also generally narrow and do not allow proper access for inspection, cleaning and drying.
Similarly, other types of thermometers, such as those used in scientific laboratory work, or commercial manufacture can become contaminated through storage in a small and convenient, but easily-contaminable, hard-to clean tubular cases. Minute amounts of chemical substances trapped in the storage case and contaminating the thermometer, can have catastrophic effects on the rate and accuracy of chemical reactions and the quality of end products obtained. Thus, cases that are easy to clean and to verify the cleanliness of are necessary for these kinds of thermometers as well.
Until recently, most designs for thermometer protective cases did not directly address the problem of cross-contamination of foods and patients through the use of thermometer. Instead, thermometer cases of the past mostly focused on protecting fragile glass mercury thermometers of the day from external contamination (such as dust) and physical shock. Many were shaped as traditional caskets, with lids. Such cases were generally bulky and, in contrast to the sheath-type cases of the present invention, had to be opened and closed whenever the user had to access the thermometer.
The cases had to protect the thermometer on all sides, and often employed padding to keep the thermometer in place. Such padding often consisted of soft porous materials that, while protecting the thermometer from breakage, greatly exacerbated sanitary concerns. Particles of food in case of food thermometers, or particles of infected flesh, such as skin flakes, in case of medical thermometers, would get caught in the padding material and contribute to continuous re-contamination of the thermometer. The porous nature of the padding material usually made proper cleaning very difficult, if not impossible task.
Newer, commonly-used top-loading sheath-type cases are much smaller, sometimes barely larger than thermometer itself. They offer solid protection for the few sensitive parts of modern thermometers and provide simple insertion and extraction. But cleanliness remains their very serious deficiency. This deficiency in top-loading cases is recognized and several attempts were made to address it.
For example, some patents teach the use of sanitizing medium within the case. In such cases, wiping members may be used to wipe off the thermometer before insertion and to seal the sanitizing medium within the case. However, there are several obvious drawbacks to implementation of such apparatus'. One issue is the use of chemicals to sanitize the utensil, such as a food thermometer, that is used to penetrate prepared foods. Some traces of the sanitizing chemical are always going to remain on thermometer's surface and get transferred into the food. To successfully sanitize the thermometer probe, such chemical must be harmful enough to bacterial cells and other living microorganisms to kill them, or inhibit their growth. Such substances can, and usually are, just as harmful to human cells as they are to bacterial cells. Many disinfectants kill bacteria by altering or damaging DNA, other work by destroying cell walls, yet others interfere with cellular metabolism. The mechanisms of function of many such sanitizing substances are still not fully understood, let alone their effects on humans. Many disinfectants are carcinogenic. At the very least any potent disinfectant will cause allergies in some people, thus making the case troublesome and legally-dangerous for use in food service settings.
Cases holding liquid disinfectant are complex and relatively expensive to make. The sanitizing medium must be regularly replaced, which can be cumbersome and expensive. Cases with sanitizing medium inside, are larger and heavier than standard cases, negating most of the advantages associated with top-loading cases. Wiping members, sometimes used in such cases to contain the fluid and to wipe the thermometer, are prone to deterioration. But even when the wiping members are in good condition, they do not reliably prevent spills of abrasive chemicals into the shirt pocket. Wiping members can also act as contaminant-traps, capturing food particles and bacteria between the layers of wiping members (where the disinfectant is absent). The contaminants are deposited between the layers when the thermometer is inserted into the case. The contaminants caught between the layers then recontaminate the thermometer as it is being taken out of the case.
The problem of case contamination has also been recently addressed by implementation of anti-microbial plastics in the construction of the case. The use of such plastics in top-loading cases of traditional closed-tube design does not solve the most important problems associated with case contamination. It does, however create an additional major problem for users and manufacturers, as discussed below.
Antimicrobial plastics are composed of polymers mixed with special disinfectants. The plastic slowly releases the disinfectant over time, inhibiting bacterial growth on the surface of the plastic. When the disinfectant runs out, the plastic permanently looses its anti-microbial characteristics. In the case of thermometer holders, it is impossible for a cook to determine how much, if any disinfectant is being released from a particular case, and when it completely runs out. The cases, are usually stored under elevated temperatures, be it inside of a pocket or by the stove. Hot thermometers are often inserted into the cases. Wet, dirty thermometers are often inserted into the cases. Thermometers scratch the case walls during every insertion and extraction. All of this causes the disinfectants to release from the case walls at accelerated rates, soon leaving anti-bacterial plastics rather impotent.
Cases made of antimicrobial plastics may initially prevent some microbial growth, but they do not disinfect the thermometer. Thus, proper safety techniques still dictate that the thermometer must be disinfected after every use, before being placed back into the case. If chemical disinfectants are used on the body of the thermometer, traces of these chemicals may react with chemical disinfectants that are being released from the walls of the case. The products of these reactions may be toxic, carcinogenic, or otherwise harmful to human body. Even if no health statistics is yet available on effects of disinfectants used in antimicrobial plastics, some customers may still be reluctant to insert a utensil with traces of chemical disinfectant into their food, and therefore reluctant to buy such a case.
Of even greater importance is the fact that anti-microbial plastics are generally limited in their anti-microbial characteristics. Anti-microbial plastics are not effective against all types of pathogenic microorganisms and will not instantly kill bacteria on contact. Even if the case is new, with still-potent anti-microbial characteristics, some bacteria may well survive for some minutes, hours, or days on the surface of the case, leading to thermometer recontamination within this time.
Some kinds of bacteria, including the most dangerous spore-forming genera of Bacillus and Clostridium, may survive exposure to disinfectants for years. In fact their spores are not only resistant to chemical disinfectants, but also to ultraviolet and gamma radiation, desiccation, lysozyme, temperature and starvation. As soon as the spores of these bacteria are transferred back into food, they spring to life, contaminating the food, and poisoning the consumer. There need not be a great number of bacterial spores for such contamination to be deadly. Even a single spore of Clostridium botulinum, if swallowed, can spring to life, multiply inside the digestive system and kill a person. Young children and people with low acidity in the digestive system are at particularly acute risk. In fact, recent studies have shown that botulism bacteria or toxin were found in up to 20% of cases thought to be caused by Sudden Infant Death Syndrome (the leading cause of death among infants who are 1 month to 1 year old). The only practical way to get rid of these bacterial and protozoan protective spores and cysts in thermometer case is to mechanically scrub and wash them away with soap and water.
If anti-microbial function of the anti-microbial plastics case performs as expected, some bacteria will die, but if the case is not regularly and thoroughly cleaned, the layer of dead bacteria and contaminants will form a protective film on the walls of the case. Antimicrobial plastic generally only affects bacteria in direct contact with the surface of the plastic. Once the protective film forms on the surface of the case, the film will act as a barrier between the new layers of bacterial contamination and the disinfecting substance. The bacteria will flourish inside the case, which will lead to thermometer contamination. In fact, any contaminant more than a few cells thick, such as a particle of meat, will likely not be affected by anti-microbial plastics. There may be inhibition of bacterial growth in place of contact with the case, but bacteria will be thriving inside and on the surface of the meat particle.
Due to the limited effectiveness of anti-microbial cases, health risks arise for consumers, and serious legal risks arise for manufacturers and distributors of such cases. Some consumers will purchase the cases under assumption that the case is 100% effective against all microorganisms on the surface of the case, or that the case will sanitize the thermometer. Some may assume that anti-microbial properties of the case do not expire with time. There is no simple way for consumers to check the case for decay or discoloration inside, and no simple way to clean it, due to the structural deficiencies described above. Thus, many will rely on manufacturer's “anti-microbial” label, assuming that the case is microbe-free until the worst happens. Then, the cook, the victim, or dead victim's representatives will sue the manufacturers and distributors of anti-microbial cases for inducing false reliance, by giving a false and unverifiable sense of security in the safety of their products. If the design of the cases had been such that the case could be opened by the cook, checked for contamination, and washed, if required, then, cooking safety would be greatly increased. Thousands of people each year would be spared from violent illness or death. This by itself would lead to decreased legal liability. But even in cases of improper sanitary technique, where the chef easily could have, but did not inspect or clean the thermometer case, the chef alone would be at fault, and the liability of manufacturers and distributors would be greatly reduced.
In light of the problems and liabilities associated with traditional thermometer cases, there is a long-standing and unsatisfied need in the art for a case that can be maintained verifiably clean, without sacrificing the all-important modern thermometer case conveniences, such as the smallest possible form factor, solid protection of the sensitive thermometer parts, and quick and easy thermometer removal and insertion without any need to open the case. Such a case should retain all its advantages in its basic form, or in conjunction with the latest sanitary advancements, such as anti-microbial plastics. In addition to that, the case should retain extremely low costs of production and ownership. The present invention achieves all of these objectives and provides numerous additional benefits for manufacturers, consumers, and society in general.